Solved

Integration of time series data

Posted on 2009-07-16
3
1,412 Views
Last Modified: 2016-02-10
Helo- I have columns of time history data as shown below. How do I do integration of these data and write in a separate column, i. e., in"Integrated values" column? Do I have to use trapizoidal rule, or simpson rule? Any example of MATLAB command or code will help. Thanks.

time Value   Integrated values
0        0.1
0.1     2
0.2     3
0.4     1
0
Comment
Question by:okd
  • 2
3 Comments
 
LVL 15

Expert Comment

by:yuk99
Comment Utility
What method to use for integration is up to you. Trapezoidal integration is build into Matlab. If you imported time as x and Value as y, you can do integration as z=trapz(x,y);
If you also need help to import/output data, please tell more details on your original data format and what you want as output. How large is the dataset? You can also attach an example here.
0
 

Author Comment

by:okd
Comment Utility
Thank you. Could you also send me how to import and output data in MATLAB. The database is like I have sent you, but it has 500 rows. I want to plot the time vs. z=trapz(x,y) values. Matlab commands for plotting and import/output data will help the most. Thanks again, - okd
0
 
LVL 15

Accepted Solution

by:
yuk99 earned 125 total points
Comment Utility
Here is the code. It read the data from tab-delimited file tsdata.txt and returns 2-column matrix data. To make it clear I put time into time vector and value into value vector (rows 2 and 3). TRAPZ function will return only one value - the total area under the curve for the whole vector. To get integrated value for every time point you can use CUMTRAPZ.
% data import

data=dlmread('tsdata.txt','\t',1,0);

% let's split variables for clarity

time=data(:,1);

value=data(:,2);

% calculating integrated values

intvalue=cumtrapz(time,value);

% plotting

plot(time,intvalue)

Open in new window

0

Featured Post

How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

Join & Write a Comment

Suggested Solutions

Title # Comments Views Activity
Help with my python script 6 143
centeredAverage challenge 8 119
tenRun challenge 28 81
mapAB Challlenge 35 83
Navigation is an important part of web design from a usability perspective. But it is often a pain when it comes to a developer’s perspective. By navigation, it often means menuing. This is less theory and more practical of how to get a specific gro…
When we want to run, execute or repeat a statement multiple times, a loop is necessary. This article covers the two types of loops in Python: the while loop and the for loop.
The goal of this video is to provide viewers with basic examples to understand and use conditional statements in the C programming language.
This theoretical tutorial explains exceptions, reasons for exceptions, different categories of exception and exception hierarchy.

728 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

9 Experts available now in Live!

Get 1:1 Help Now